Foldable backpack



FIG. 1 is a perspective view of a foldable backpack showing my present design in a folded and closed position;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof;

FIG. 7 is a bottom view thereof; and,

FIG. 8 is a side view thereof in an alternative, open position.

The broken lines illustrate portions of the foldable backpack and form no part of the claimed design. 

CLAIM The ornamental design for a foldable backpack, as shown and described. 